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Memo to Steve Renner <br /> Coal Basin Examination <br /> page 4 <br /> of an old topographic swale. I recommend that these seeps be <br /> developed by excavating and backfilling them with gravel to promote <br /> better drainage and decrease residence time for groundwater. This <br /> should stabilize the material and help to prevent mine drainage <br /> acidity problems. Finally, the small triangle of ground below the <br /> newly aligned ditch should be graded to drain towards the southeast <br /> and -into the ditch. It will be difficult to achieve more than 1%� <br /> grade in this area. Hopefully by completing this combination of <br /> improvements, less saturation will occur due to ponding of spring <br /> melt waters in this poorly drained bog area. <br /> Mr. Dulaney expressed his dismay at redisturbing the old access <br /> road which he suggested had achieved the sort of natural slope <br /> readjustment they believe all roads at Coal Basin should be allowed <br /> to attain in final reclamation. Tony and I observed that the coal <br /> refuse pile is required to have a permanent diversion. The <br /> operators representatives also suggested they'd like to allow the <br /> road to drain in "sheet flow" over the outslope and into Dutch <br /> Creek, approximately 100 feet down its course from the disturbed <br /> area. I believe this is not desirable and recommended against it <br /> because "sheet flow" without a concrete pan or cleaned resistant <br /> bedrock inevitably results in gully formation and increased <br /> sediment generation. <br /> cc: Tony Waldron <br /> Larry Routten <br /> Doc: M:\MIN\JAP\DUTCHCRK.WPF <br /> JP/jP <br />